Switching systems such as PABXs or central office switching systems offering special services are often networked. Some of those special services are speed call or call-by-name. While speed call and call-by-name services are well established within the confines and control of a single PABX, when a speed call or call-by-name directory entry is desired to be offered to users connected to more than one PABX, its management has been difficult.
For example, one type of such a network could utilize a central management system containing a list of all of the directory data entries of all the switching systems to which each is applied. The data entries relating to each designated switching system would be downloaded to the designated system. All changes, such as a move of a user to a different physical location would require modification of the entry at the central management system and downloading of new data to each affected switching system from the central location. This would require active control by an operator at the central management system location and individual control of the data entries at each specific switching system.
In another system the central control could avoid maintaining a copy of the directory data entry list, but instead keep separate lists only at each switching system. However in order to provide a common speed dial or dial by name facility to other switching systems, retrieval and retransmission of the relevant data would have to be effected from the central management system.
The above-noted systems would not facilitate the provision of common directory entries for various groups of switching systems connected in the network, in which each group could contain reference to some similarly identified switching systems. In other words "communities of interest" of the various directory data entries are not facilitated.
In addition, the above-described systems would not allow persons such as local telephone users or local telephone operators to make directory changes at a local switching system which automatically changes the corresponding data in all directories in all local switching systems in a particular community of interest on a global basis within the network.
The above-described systems do not facilitate an operator of a management system to make a directory change at the management system only once, resulting in change of all of the directory entries relating to that changed data entry in all switching systems in a community of interest of switching systems, at once.